Numerous industrial processes require that each of a multiplicity of identical objects be fitted to a respective receptacle in a predetermined position. This fitting-together must be carried out repeatedly and at high speed.
This is for example the case in capping bottles, which is done by moving the upright full bottles underneath a station at which caps are fitted to them, for example by press-fitting. This is also the procedure for fitting primer caps in the bases of ammunition casings, or in receptacles serving for subsequent transfer to such casings. Such a procedure is also used in numerous other areas, as for example in electronics for the placement and attachment of elements in printed circuits.
Most frequently these operations are carried out in steps, the movement of the receptacles being interrupted at each fitting operation since this operation takes place at a fixed station. To fit primer caps into the bases of casings, the casings are moved in a row one after the other under a fitting press which feeds the primer caps, for example from a hopper, one by one to a slide arrangement. When a casing is in the press, the movement of the row of casings is stopped and the press pushes the primer cap with the slide arrangement into the base of the thus arrested casing. The row of casings is then advanced one step, by the distance between two casings, and the operation is repeated. It is thus possible to fit about 80 to 120 caps per minute into the bases of respective casings.
This known procedure has several disadvantages. One of these disadvantages is that the stepwise movement of the receptacles is very hard on the conveyor mechanism and is quite noisy. Another disadvantage is that the procedure is slow, since mechanical considerations make a high production rate impossible. Even so this procedure is so fast that it creates feed problems. It is therefore possible that some casings are not fitted with a primer cap and that the unloaded casings must be found and culled out.